No, Azelf will not come back in Pokémon Diamond once you have defeated it in a battle or you have ran from the battle. Mesprit, 1 of the 2 Pokémon that you encounter in a cave, it will flee once you interact with it but you will be able to run into it as you're walking across the region.
Its not Azelf its Mesprit that flees and you get it by using the Pokemon tracker app and you wil need a Pokemon with mean look so Mesprit does not flee.
After she flees from the island, she roams the sinnoh region. Then you can use your poketch app that you use to find mesprit, and hunt it down.
u can give ur Pokemon quick claw
Rotom in old Chateau, Cresselia around Sinnoh because it flees, Giratina in Turnback cave, Regigigas in Snowpoint Temple, Heatran in Stark Mountain, Phione, Manaphy, Palkia or Dialga on Spear Pillar, Azelf at Lake Valor, Mesprit at Lake Verity then chase through Sinnoh like Cresselia and Uxie at Lake Acuity.
There is no TM for it. You have to catch a golbat that knows it. I can see your looking for Mesprit or Cressila. Train the golbat to 100 speed or your mean look will perform after it flees lol. ~Wariolink~ Pokemaster
it depennds check all the islands ;)
it roams. u have to get lucky and catch i with the masterball because it flees.
You find them all at separate lakes. You can catch Uxie and Azelf at their lakes. Mesprit flees again when you go to her lake. You need to use the map marker poketch app to find it. PS: Don't fly towards the Mesprit. It will go to a different spot then. Use your bike or run to get to it.
for Ruby: you have to dive near the circle of rocks on i think route 128 go in the underground cavern and eventualy battle maxy after that groudoun flees to the cave of origins and you are allowed to go inside and catch him there are also rare Pokemon in there like sableye and mawile. once you catch him or defeat him you can go to the 8th gym
The trio also known as Uxie, Azelf and Mesprit are found in the three lakes (Valor, Verity and Acuity) you will need surf and Pokemon around the 50s since they are all level 50. In the middle of the water you will see a small cavern inside there will be one of the three. However when you click on Mesprit it will make its cry and it will be added to your pokedex as being seen but not caught because it now is roaming around the sinnoh. After Mesprit flies away Rowan will come in and talk about a load of rubbish and then he leaves. To catch Mesprit I would suggest if you have your master ball to use it on him if not it becomes very hard to get, because when you see it, it doesn't battle it lets you have one turn and flees. If you have used your master ball then you will need a Pokemon that knows mean look such as Golbat. To track Mesprit down you will need the marking map app, to obtain it you need to go to the poke tech company in Jubilife City.
To find Dialga and Palkia in Pokemon Plaltinum, first you need to get the marking map poketch app from the president of the poketch company in Jubilife city. Then you need to get all the legendarys of the lakes. (Uxie, Azelf, Mespirit) Uxie and Azelf are hard enough to catch while mespirit is three times as hard to catch. It flees as soon as possible, It flies all over the sinnoh region (that is why you got the marking map). Then go defeat the elite 4 and the champion. Next and all the legendarys to your party and go to the ruins and talk to cynthia's grandmother and then go to spear pillar. Dialga and palkia are lv70 so be prepared to catch them. Go to the end the place(near the whirlpool that Giritina created) and you'll find a floating blue diamond and talk to it and you fight dialga! After you have fleed, defeated or caught Dialga, exit and go back and there will be a floating pink diamond and repeat the process.
The Poochyena flees when you are one hit away from KO